155714Skris/* crypto/asn1/a_int.c */ 255714Skris/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 355714Skris * All rights reserved. 455714Skris * 555714Skris * This package is an SSL implementation written 655714Skris * by Eric Young (eay@cryptsoft.com). 755714Skris * The implementation was written so as to conform with Netscapes SSL. 8280297Sjkim * 955714Skris * This library is free for commercial and non-commercial use as long as 1055714Skris * the following conditions are aheared to. The following conditions 1155714Skris * apply to all code found in this distribution, be it the RC4, RSA, 1255714Skris * lhash, DES, etc., code; not just the SSL code. The SSL documentation 1355714Skris * included with this distribution is covered by the same copyright terms 1455714Skris * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15280297Sjkim * 1655714Skris * Copyright remains Eric Young's, and as such any Copyright notices in 1755714Skris * the code are not to be removed. 1855714Skris * If this package is used in a product, Eric Young should be given attribution 1955714Skris * as the author of the parts of the library used. 2055714Skris * This can be in the form of a textual message at program startup or 2155714Skris * in documentation (online or textual) provided with the package. 22280297Sjkim * 2355714Skris * Redistribution and use in source and binary forms, with or without 2455714Skris * modification, are permitted provided that the following conditions 2555714Skris * are met: 2655714Skris * 1. Redistributions of source code must retain the copyright 2755714Skris * notice, this list of conditions and the following disclaimer. 2855714Skris * 2. Redistributions in binary form must reproduce the above copyright 2955714Skris * notice, this list of conditions and the following disclaimer in the 3055714Skris * documentation and/or other materials provided with the distribution. 3155714Skris * 3. All advertising materials mentioning features or use of this software 3255714Skris * must display the following acknowledgement: 3355714Skris * "This product includes cryptographic software written by 3455714Skris * Eric Young (eay@cryptsoft.com)" 3555714Skris * The word 'cryptographic' can be left out if the rouines from the library 3655714Skris * being used are not cryptographic related :-). 37280297Sjkim * 4. If you include any Windows specific code (or a derivative thereof) from 3855714Skris * the apps directory (application code) you must include an acknowledgement: 3955714Skris * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40280297Sjkim * 4155714Skris * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 4255714Skris * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 4355714Skris * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 4455714Skris * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 4555714Skris * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 4655714Skris * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 4755714Skris * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 4855714Skris * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 4955714Skris * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 5055714Skris * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 5155714Skris * SUCH DAMAGE. 52280297Sjkim * 5355714Skris * The licence and distribution terms for any publically available version or 5455714Skris * derivative of this code cannot be changed. i.e. this code cannot simply be 5555714Skris * copied and put under another distribution licence 5655714Skris * [including the GNU Public Licence.] 5755714Skris */ 5855714Skris 5955714Skris#include <stdio.h> 6055714Skris#include "cryptlib.h" 6155714Skris#include <openssl/asn1.h> 62160814Ssimon#include <openssl/bn.h> 6355714Skris 64238405SjkimASN1_INTEGER *ASN1_INTEGER_dup(const ASN1_INTEGER *x) 65280297Sjkim{ 66280297Sjkim return M_ASN1_INTEGER_dup(x); 67280297Sjkim} 6859191Skris 69238405Sjkimint ASN1_INTEGER_cmp(const ASN1_INTEGER *x, const ASN1_INTEGER *y) 70280297Sjkim{ 71280297Sjkim int neg, ret; 72280297Sjkim /* Compare signs */ 73280297Sjkim neg = x->type & V_ASN1_NEG; 74280297Sjkim if (neg != (y->type & V_ASN1_NEG)) { 75280297Sjkim if (neg) 76280297Sjkim return -1; 77280297Sjkim else 78280297Sjkim return 1; 79280297Sjkim } 8059191Skris 81280297Sjkim ret = ASN1_STRING_cmp(x, y); 82142425Snectar 83280297Sjkim if (neg) 84280297Sjkim return -ret; 85280297Sjkim else 86280297Sjkim return ret; 87280297Sjkim} 88142425Snectar 89280297Sjkim/*- 9068651Skris * This converts an ASN1 INTEGER into its content encoding. 9155714Skris * The internal representation is an ASN1_STRING whose data is a big endian 9255714Skris * representation of the value, ignoring the sign. The sign is determined by 93280297Sjkim * the type: V_ASN1_INTEGER for positive and V_ASN1_NEG_INTEGER for negative. 9455714Skris * 9555714Skris * Positive integers are no problem: they are almost the same as the DER 9655714Skris * encoding, except if the first byte is >= 0x80 we need to add a zero pad. 9755714Skris * 9855714Skris * Negative integers are a bit trickier... 9955714Skris * The DER representation of negative integers is in 2s complement form. 100280297Sjkim * The internal form is converted by complementing each octet and finally 10155714Skris * adding one to the result. This can be done less messily with a little trick. 10255714Skris * If the internal form has trailing zeroes then they will become FF by the 103280297Sjkim * complement and 0 by the add one (due to carry) so just copy as many trailing 10455714Skris * zeros to the destination as there are in the source. The carry will add one 10555714Skris * to the last none zero octet: so complement this octet and add one and finally 10655714Skris * complement any left over until you get to the start of the string. 10755714Skris * 10855714Skris * Padding is a little trickier too. If the first bytes is > 0x80 then we pad 10955714Skris * with 0xff. However if the first byte is 0x80 and one of the following bytes 11055714Skris * is non-zero we pad with 0xff. The reason for this distinction is that 0x80 11155714Skris * followed by optional zeros isn't padded. 11255714Skris */ 11355714Skris 11468651Skrisint i2c_ASN1_INTEGER(ASN1_INTEGER *a, unsigned char **pp) 115280297Sjkim{ 116280297Sjkim int pad = 0, ret, i, neg; 117280297Sjkim unsigned char *p, *n, pb = 0; 11855714Skris 119280297Sjkim if (a == NULL) 120280297Sjkim return (0); 121280297Sjkim neg = a->type & V_ASN1_NEG; 122280297Sjkim if (a->length == 0) 123280297Sjkim ret = 1; 124280297Sjkim else { 125280297Sjkim ret = a->length; 126280297Sjkim i = a->data[0]; 127284283Sjkim if (ret == 1 && i == 0) 128284283Sjkim neg = 0; 129280297Sjkim if (!neg && (i > 127)) { 130280297Sjkim pad = 1; 131280297Sjkim pb = 0; 132280297Sjkim } else if (neg) { 133280297Sjkim if (i > 128) { 134280297Sjkim pad = 1; 135280297Sjkim pb = 0xFF; 136280297Sjkim } else if (i == 128) { 137280297Sjkim /* 138280297Sjkim * Special case: if any other bytes non zero we pad: 139280297Sjkim * otherwise we don't. 140280297Sjkim */ 141280297Sjkim for (i = 1; i < a->length; i++) 142280297Sjkim if (a->data[i]) { 143280297Sjkim pad = 1; 144280297Sjkim pb = 0xFF; 145280297Sjkim break; 146280297Sjkim } 147280297Sjkim } 148280297Sjkim } 149280297Sjkim ret += pad; 150280297Sjkim } 151280297Sjkim if (pp == NULL) 152280297Sjkim return (ret); 153280297Sjkim p = *pp; 15455714Skris 155280297Sjkim if (pad) 156280297Sjkim *(p++) = pb; 157280297Sjkim if (a->length == 0) 158280297Sjkim *(p++) = 0; 159280297Sjkim else if (!neg) 160280297Sjkim memcpy(p, a->data, (unsigned int)a->length); 161280297Sjkim else { 162280297Sjkim /* Begin at the end of the encoding */ 163280297Sjkim n = a->data + a->length - 1; 164280297Sjkim p += a->length - 1; 165280297Sjkim i = a->length; 166280297Sjkim /* Copy zeros to destination as long as source is zero */ 167284283Sjkim while (!*n && i > 1) { 168280297Sjkim *(p--) = 0; 169280297Sjkim n--; 170280297Sjkim i--; 171280297Sjkim } 172280297Sjkim /* Complement and increment next octet */ 173280297Sjkim *(p--) = ((*(n--)) ^ 0xff) + 1; 174280297Sjkim i--; 175280297Sjkim /* Complement any octets left */ 176280297Sjkim for (; i > 0; i--) 177280297Sjkim *(p--) = *(n--) ^ 0xff; 178280297Sjkim } 17955714Skris 180280297Sjkim *pp += ret; 181280297Sjkim return (ret); 182280297Sjkim} 18355714Skris 18468651Skris/* Convert just ASN1 INTEGER content octets to ASN1_INTEGER structure */ 18568651Skris 186160814SsimonASN1_INTEGER *c2i_ASN1_INTEGER(ASN1_INTEGER **a, const unsigned char **pp, 187280297Sjkim long len) 188280297Sjkim{ 189280297Sjkim ASN1_INTEGER *ret = NULL; 190280297Sjkim const unsigned char *p, *pend; 191280297Sjkim unsigned char *to, *s; 192280297Sjkim int i; 19368651Skris 194280297Sjkim if ((a == NULL) || ((*a) == NULL)) { 195280297Sjkim if ((ret = M_ASN1_INTEGER_new()) == NULL) 196280297Sjkim return (NULL); 197280297Sjkim ret->type = V_ASN1_INTEGER; 198280297Sjkim } else 199280297Sjkim ret = (*a); 20068651Skris 201280297Sjkim p = *pp; 202280297Sjkim pend = p + len; 20368651Skris 204280297Sjkim /* 205280297Sjkim * We must OPENSSL_malloc stuff, even for 0 bytes otherwise it signifies 206280297Sjkim * a missing NULL parameter. 207280297Sjkim */ 208280297Sjkim s = (unsigned char *)OPENSSL_malloc((int)len + 1); 209280297Sjkim if (s == NULL) { 210280297Sjkim i = ERR_R_MALLOC_FAILURE; 211280297Sjkim goto err; 212280297Sjkim } 213280297Sjkim to = s; 214280297Sjkim if (!len) { 215280297Sjkim /* 216280297Sjkim * Strictly speaking this is an illegal INTEGER but we tolerate it. 217280297Sjkim */ 218280297Sjkim ret->type = V_ASN1_INTEGER; 219280297Sjkim } else if (*p & 0x80) { /* a negative number */ 220280297Sjkim ret->type = V_ASN1_NEG_INTEGER; 221280297Sjkim if ((*p == 0xff) && (len != 1)) { 222280297Sjkim p++; 223280297Sjkim len--; 224280297Sjkim } 225280297Sjkim i = len; 226280297Sjkim p += i - 1; 227280297Sjkim to += i - 1; 228280297Sjkim while ((!*p) && i) { 229280297Sjkim *(to--) = 0; 230280297Sjkim i--; 231280297Sjkim p--; 232280297Sjkim } 233280297Sjkim /* 234280297Sjkim * Special case: if all zeros then the number will be of the form FF 235280297Sjkim * followed by n zero bytes: this corresponds to 1 followed by n zero 236280297Sjkim * bytes. We've already written n zeros so we just append an extra 237280297Sjkim * one and set the first byte to a 1. This is treated separately 238280297Sjkim * because it is the only case where the number of bytes is larger 239280297Sjkim * than len. 240280297Sjkim */ 241280297Sjkim if (!i) { 242280297Sjkim *s = 1; 243280297Sjkim s[len] = 0; 244280297Sjkim len++; 245280297Sjkim } else { 246280297Sjkim *(to--) = (*(p--) ^ 0xff) + 1; 247280297Sjkim i--; 248280297Sjkim for (; i > 0; i--) 249280297Sjkim *(to--) = *(p--) ^ 0xff; 250280297Sjkim } 251280297Sjkim } else { 252280297Sjkim ret->type = V_ASN1_INTEGER; 253280297Sjkim if ((*p == 0) && (len != 1)) { 254280297Sjkim p++; 255280297Sjkim len--; 256280297Sjkim } 257280297Sjkim memcpy(s, p, (int)len); 258280297Sjkim } 25955714Skris 260280297Sjkim if (ret->data != NULL) 261280297Sjkim OPENSSL_free(ret->data); 262280297Sjkim ret->data = s; 263280297Sjkim ret->length = (int)len; 264280297Sjkim if (a != NULL) 265280297Sjkim (*a) = ret; 266280297Sjkim *pp = pend; 267280297Sjkim return (ret); 268280297Sjkim err: 269280297Sjkim ASN1err(ASN1_F_C2I_ASN1_INTEGER, i); 270280297Sjkim if ((ret != NULL) && ((a == NULL) || (*a != ret))) 271280297Sjkim M_ASN1_INTEGER_free(ret); 272280297Sjkim return (NULL); 273280297Sjkim} 27455714Skris 275280297Sjkim/* 276280297Sjkim * This is a version of d2i_ASN1_INTEGER that ignores the sign bit of ASN1 277280297Sjkim * integers: some broken software can encode a positive INTEGER with its MSB 278280297Sjkim * set as negative (it doesn't add a padding zero). 27955714Skris */ 28055714Skris 281160814SsimonASN1_INTEGER *d2i_ASN1_UINTEGER(ASN1_INTEGER **a, const unsigned char **pp, 282280297Sjkim long length) 283280297Sjkim{ 284280297Sjkim ASN1_INTEGER *ret = NULL; 285280297Sjkim const unsigned char *p; 286280297Sjkim unsigned char *s; 287280297Sjkim long len; 288280297Sjkim int inf, tag, xclass; 289280297Sjkim int i; 29055714Skris 291280297Sjkim if ((a == NULL) || ((*a) == NULL)) { 292280297Sjkim if ((ret = M_ASN1_INTEGER_new()) == NULL) 293280297Sjkim return (NULL); 294280297Sjkim ret->type = V_ASN1_INTEGER; 295280297Sjkim } else 296280297Sjkim ret = (*a); 29755714Skris 298280297Sjkim p = *pp; 299280297Sjkim inf = ASN1_get_object(&p, &len, &tag, &xclass, length); 300280297Sjkim if (inf & 0x80) { 301280297Sjkim i = ASN1_R_BAD_OBJECT_HEADER; 302280297Sjkim goto err; 303280297Sjkim } 30455714Skris 305280297Sjkim if (tag != V_ASN1_INTEGER) { 306280297Sjkim i = ASN1_R_EXPECTING_AN_INTEGER; 307280297Sjkim goto err; 308280297Sjkim } 30955714Skris 310280297Sjkim /* 311280297Sjkim * We must OPENSSL_malloc stuff, even for 0 bytes otherwise it signifies 312280297Sjkim * a missing NULL parameter. 313280297Sjkim */ 314280297Sjkim s = (unsigned char *)OPENSSL_malloc((int)len + 1); 315280297Sjkim if (s == NULL) { 316280297Sjkim i = ERR_R_MALLOC_FAILURE; 317280297Sjkim goto err; 318280297Sjkim } 319280297Sjkim ret->type = V_ASN1_INTEGER; 320280297Sjkim if (len) { 321280297Sjkim if ((*p == 0) && (len != 1)) { 322280297Sjkim p++; 323280297Sjkim len--; 324280297Sjkim } 325280297Sjkim memcpy(s, p, (int)len); 326280297Sjkim p += len; 327280297Sjkim } 32855714Skris 329280297Sjkim if (ret->data != NULL) 330280297Sjkim OPENSSL_free(ret->data); 331280297Sjkim ret->data = s; 332280297Sjkim ret->length = (int)len; 333280297Sjkim if (a != NULL) 334280297Sjkim (*a) = ret; 335280297Sjkim *pp = p; 336280297Sjkim return (ret); 337280297Sjkim err: 338280297Sjkim ASN1err(ASN1_F_D2I_ASN1_UINTEGER, i); 339280297Sjkim if ((ret != NULL) && ((a == NULL) || (*a != ret))) 340280297Sjkim M_ASN1_INTEGER_free(ret); 341280297Sjkim return (NULL); 342280297Sjkim} 34355714Skris 34455714Skrisint ASN1_INTEGER_set(ASN1_INTEGER *a, long v) 345280297Sjkim{ 346280297Sjkim int j, k; 347280297Sjkim unsigned int i; 348280297Sjkim unsigned char buf[sizeof(long) + 1]; 349280297Sjkim long d; 35055714Skris 351280297Sjkim a->type = V_ASN1_INTEGER; 352280297Sjkim if (a->length < (int)(sizeof(long) + 1)) { 353280297Sjkim if (a->data != NULL) 354280297Sjkim OPENSSL_free(a->data); 355280297Sjkim if ((a->data = 356280297Sjkim (unsigned char *)OPENSSL_malloc(sizeof(long) + 1)) != NULL) 357280297Sjkim memset((char *)a->data, 0, sizeof(long) + 1); 358280297Sjkim } 359280297Sjkim if (a->data == NULL) { 360280297Sjkim ASN1err(ASN1_F_ASN1_INTEGER_SET, ERR_R_MALLOC_FAILURE); 361280297Sjkim return (0); 362280297Sjkim } 363280297Sjkim d = v; 364280297Sjkim if (d < 0) { 365280297Sjkim d = -d; 366280297Sjkim a->type = V_ASN1_NEG_INTEGER; 367280297Sjkim } 36855714Skris 369280297Sjkim for (i = 0; i < sizeof(long); i++) { 370280297Sjkim if (d == 0) 371280297Sjkim break; 372280297Sjkim buf[i] = (int)d & 0xff; 373280297Sjkim d >>= 8; 374280297Sjkim } 375280297Sjkim j = 0; 376280297Sjkim for (k = i - 1; k >= 0; k--) 377280297Sjkim a->data[j++] = buf[k]; 378280297Sjkim a->length = j; 379280297Sjkim return (1); 380280297Sjkim} 38155714Skris 382238405Sjkimlong ASN1_INTEGER_get(const ASN1_INTEGER *a) 383280297Sjkim{ 384280297Sjkim int neg = 0, i; 385280297Sjkim long r = 0; 38655714Skris 387280297Sjkim if (a == NULL) 388280297Sjkim return (0L); 389280297Sjkim i = a->type; 390280297Sjkim if (i == V_ASN1_NEG_INTEGER) 391280297Sjkim neg = 1; 392280297Sjkim else if (i != V_ASN1_INTEGER) 393280297Sjkim return -1; 39455714Skris 395280297Sjkim if (a->length > (int)sizeof(long)) { 396280297Sjkim /* hmm... a bit ugly, return all ones */ 397280297Sjkim return -1; 398280297Sjkim } 399280297Sjkim if (a->data == NULL) 400280297Sjkim return 0; 40155714Skris 402280297Sjkim for (i = 0; i < a->length; i++) { 403280297Sjkim r <<= 8; 404280297Sjkim r |= (unsigned char)a->data[i]; 405280297Sjkim } 406280297Sjkim if (neg) 407280297Sjkim r = -r; 408280297Sjkim return (r); 409280297Sjkim} 410280297Sjkim 411238405SjkimASN1_INTEGER *BN_to_ASN1_INTEGER(const BIGNUM *bn, ASN1_INTEGER *ai) 412280297Sjkim{ 413280297Sjkim ASN1_INTEGER *ret; 414280297Sjkim int len, j; 41555714Skris 416280297Sjkim if (ai == NULL) 417280297Sjkim ret = M_ASN1_INTEGER_new(); 418280297Sjkim else 419280297Sjkim ret = ai; 420280297Sjkim if (ret == NULL) { 421280297Sjkim ASN1err(ASN1_F_BN_TO_ASN1_INTEGER, ERR_R_NESTED_ASN1_ERROR); 422280297Sjkim goto err; 423280297Sjkim } 424284283Sjkim if (BN_is_negative(bn) && !BN_is_zero(bn)) 425280297Sjkim ret->type = V_ASN1_NEG_INTEGER; 426280297Sjkim else 427280297Sjkim ret->type = V_ASN1_INTEGER; 428280297Sjkim j = BN_num_bits(bn); 429280297Sjkim len = ((j == 0) ? 0 : ((j / 8) + 1)); 430280297Sjkim if (ret->length < len + 4) { 431280297Sjkim unsigned char *new_data = OPENSSL_realloc(ret->data, len + 4); 432280297Sjkim if (!new_data) { 433280297Sjkim ASN1err(ASN1_F_BN_TO_ASN1_INTEGER, ERR_R_MALLOC_FAILURE); 434280297Sjkim goto err; 435280297Sjkim } 436280297Sjkim ret->data = new_data; 437280297Sjkim } 438280297Sjkim ret->length = BN_bn2bin(bn, ret->data); 439280297Sjkim /* Correct zero case */ 440280297Sjkim if (!ret->length) { 441280297Sjkim ret->data[0] = 0; 442280297Sjkim ret->length = 1; 443280297Sjkim } 444280297Sjkim return (ret); 445280297Sjkim err: 446280297Sjkim if (ret != ai) 447280297Sjkim M_ASN1_INTEGER_free(ret); 448280297Sjkim return (NULL); 449280297Sjkim} 45055714Skris 451238405SjkimBIGNUM *ASN1_INTEGER_to_BN(const ASN1_INTEGER *ai, BIGNUM *bn) 452280297Sjkim{ 453280297Sjkim BIGNUM *ret; 45455714Skris 455280297Sjkim if ((ret = BN_bin2bn(ai->data, ai->length, bn)) == NULL) 456280297Sjkim ASN1err(ASN1_F_ASN1_INTEGER_TO_BN, ASN1_R_BN_LIB); 457280297Sjkim else if (ai->type == V_ASN1_NEG_INTEGER) 458280297Sjkim BN_set_negative(ret, 1); 459280297Sjkim return (ret); 460280297Sjkim} 46168651Skris 46268651SkrisIMPLEMENT_STACK_OF(ASN1_INTEGER) 463280297Sjkim 46468651SkrisIMPLEMENT_ASN1_SET_OF(ASN1_INTEGER) 465